Should you vaccinate very young calves?
Heather Smith Thomas
In the 2-week old calf, there are two things you need to be concerned about. One is age, the other is colostrum intake. Typically, even in a calf that got no colostrum [and no maternal antibodies to interfere with building its own immunity], the response for making antibodies [when vaccinated early] is not great under 3 weeks of age.